Harlan High School Principal Reginald Evans, with CTA Bus Tracker, Friday, April 20, 2012 . | John H. White~Sun-Times.

The excitement of school dismissal is different in Chicago’s crime-ridden neighborhoods.

Students aren’t thinking about what’s for dinner, if they’ll pass a math test or whether to talk to the cute girl in class.

Some are just thinking about the best way to get home without running into gang-bangers, witnessing a drug deal, getting robbed or shot.

That’s what led Chicago Public Schools to team up with the CTA in getting Bus Tracker displays inside the exits of 36 high schools.

“Around 1 or 1:30 p.m., these kids are thinking, ‘How am I going to get home?’ ” Harlan High School Principal Reginald Evans said. “You’re in class trying to learn, and if there has been a problem out here on these corners, then it’s just survival mode, trying to think, ‘Do I go this way or that way’.”

Harlan, near 96th Street and Michigan Avenue in Roseland, was the test school for the Bus Tracker system, and 35 schools followed suit on March 31, CPS said.

The schools were chosen because they have a high number of students taking public transportation, CPS says, but some are also in high crime areas.

To Evans, there’s a simple logic: The less time students spend hanging out on the streets waiting for their buses, the less likely they are to be the victims of crime or get into trouble. Now, students can stay inside and step outside just in time to catch the bus.

At Harlan, the monitor is near a safety desk. There’s a bus stop right outside the school, but also a bus depot at 95th and Michigan and nearby train station at 95th and State.

But standing around schools in high-crime areas can make you a target, and it’s something Harlan is dealing with successfully, including at night events such as dances and games.

“My staff and I, we go out at the end of every school day and we don’t let kids just stand around here,” Evans said. “Everybody’s gotta go home. Stay in here, go to tutoring or to your clubs, but the minute you step outside here, go home.”

After the pilot, CPS learned Harlan students felt safer about after-school programs knowing that they didn’t have to wait at the bus stop for a long time.

And there’s a possibility the monitors will expand to other schools in the future, CPS said. The cost: about $7,000 per school for a total cost of $250,000, funded by a combination of grants and CPS funds.

Other schools now featuring the monitors include Crane, Simeon, Hyde Park Career Academy and Fenger.